Belt driving device, driving device, method, image forming apparatus

A belt driving device is provided and includes a plurality of rollers including a driving roller. A belt is configured to be tensioned by the plurality of rollers, and to be driven by the driving roller. The driving roller is arranged adjacent to where an outside body contacts an outer surface of the belt. A pair of fluctuation absorbing members may be configured to absorb tensional fluctuation of the belt at an upstream and a downstream of a cleaning member in a direction which the belt is driven. A detecting means may be utilized to detect a driving load of one of the driving roller and the outside roller and a controller is configured to drive another roller of the driving roller and the outside roller based on the driving load detected by the detecting means. An outside roller may be configured to contact an outer surface of the belt and to be driven by a second motor; a controller configured to control the second motor by a less loop gain than a loop gain to control the first motor.